1. Field of the Invention
The present invention relates generally to vibratory material handling equipment such as vibratory feeders, screens, grizzleys, conveyors, foundry shakeouts and packers. More particularly, the invention relates to a vibratory device operable as a two mass vibratory system.
2. Description of the Prior Art
There are many proposals both in the prior patent art and in commercial use for the construction of vibratory material handling equipment. The basic differences in these equipment proposals lie in different ways for mounting the work member which is vibrated, such as a trough for feeding material, and differences in the technique by which vibrations are imparted to the work member.
One extensively used device for generating and transmitting vibrations to the work member involves use of an eccentric weight secured to a rotating shaft. The shaft may be the shaft of an electric motor or the shaft may be separate and belt driven by a motor spaced from the shaft. With a separate shaft that is belt driven the shaft itself may be easily formed to have an eccentric portion. More than one eccentric weight may be secured to a rotating shaft to produce vibratory work energy. All of this is known in the prior art.
There are a variety of teachings in the prior art for transmitting the generated vibratory work energy from the exciter to the work member.
It is also known in the prior art and quite extensively used commercially to have fixed angle leaf springs supporting the work member and exciter as a unit above a mounting base. In some vibratory equipment the equipment is suspended or supported on isolating springs with the exciter and work member operating as a two mass vibrating system. In such a system the exciter acts as one mass and the work member as a second mass, the masses designed relative to the natural frequency of the overall system.